"WWF believes the proposal is driven by Russia's blatant disregard for the environment and its desire to cheaply transport its oil, whose production is booming, through the Baltic Sea and western European waters," it said yesterday.

Russian officials in Moscow were not immediately available for comment.

The protection plan - supported by the European Union, the United States and most other countries in the IMO - is aimed at giving a special status to the Baltic and to seas around Ecuador's Galapagos Islands and Spain's Canary Islands.

It would designate them as Particularly Sensitive Sea Areas. Ships passing through would have to take special safety measures to be decided by the IMO, a United Nations agency.

Every day hundreds of oil tankers, many in a similar condition to that of the ageing Prestige which sank off the coast of Spain in 2002 and caused a major ecological and social disaster, travel along Baltic routes from Russia, the WWF said.

The Prestige disaster killed 300,000 birds, put hundreds of fishermen along the Atlantic coasts of Spain and France out of work for months, and cost some five billion euros (3.3 billion pounds) in clean-up and environmental costs.

WWF specialists say Russia - which has won support from Liberia and Panama which both have large tanker fleets - fears that the maritime protection measures would push up the cost of transporting its oil by sea and make it less competitive.

Environmentalists fear other members of the IMO, which normally operates on a consensus basis, might hesitate to break tradition by calling a vote to force the plan through.

If Russia and its allies blocked agreement, the Swiss-based WWF said, it would be "a significant blow to efforts to protect vulnerable marine areas from major oil spills."

The Baltic "is one of the planet's smallest and most vulnerable seas, where there is imminent risk of a similar devastating oil accident," said WWF marine expert Simon Cripps.

The eastern Pacific Galapagos, where Charles Darwin in the 1830s first found the evidence for evolution, are the home to hundreds of unique varieties of animal, bird and plant life.

An oil spill there three years ago caused huge damage, and the islands - like the Canaries in the Atlantic off West Africa and home to endangered pilot whales - face constant danger from similar and more devastating accidents, Cripps said.